Joint structure of overlapped sheets



July 3, 1962 G. T. FACER ETAL JOINT STRUCTURE OF OVERLAPPED SHEETS FiledJan. 25, 1960 INVENTORS.

GRANT 7. PACER STANLEY A. lLPATR/CK ORNEY United States Patent M3,041,784 JOINT STRUCTURE OF OVERLAPPED SHEETS Grant T. Facer,Lafayette, Elalifi, and Stanley A. Kilpatrick, Spokane, Wash, assignorsto Kaiser Aluminum & Chemical Corporation, Oakland, Calif., acorporation of Delaware Filed Jan. 25, 1960, Ser. No. 4,347 6 Claims.(Cl. 50-420) This invention relates to roofing structures. Moreparticularly it is concerned with providing a novel joint in roofingstructures employing joints of the standing lap type.

Accordingly, it is a primary purpose of this invention to provide animproved joint of the standing lap type for roofing sheets which issubstantially weatherproof and wherein the roofing sheets can be readilymanufactured while at the same time using a minimum amount of materialin the parts of the sheets used in the joint.

Other purposes and advantages of the instant invention Will become moreapparent from a review of the following detailed description when takenin conjunction with the appended drawings wherein:

FIGURE 1 is a broken fragmentary perspective view of a typical roofinginstallation involving the principles of the instant invention;

FIGURE 2 is an enlarged partial sectional view of one marginal side edgeof one of the roofing sheets shown in FIGURE 1;

FIGURE 3 is an enlarged partial sectional view of the opposed marginalside edge of one of the roofing sheets shown in FIGURE 1; and

FIGURE 4 is an enlarged fragmentary sectional view of a roofing jointinstallational and discloses the manner in which the marginal side edgesof the roofing sheets are overlapped to form the joint of the instantinvention and with parts broken away and with certain of said sheetsbeing shown in dotted lines.

Since the lap joint of the instant invention is adapted for use withboth roofing and siding sheets employed as coverings for buildingstructures, the word roofing as used in the specification and claims isto be construed as covering siding as well as roofing sheets and thejoints therefor.

'In one advantageous embodiment of the invention, the lap joint of theinstant invention is used for roofing sheets 1 preferably made ofthin-gauge aluminum and provided with a plurality of upstandingfiat-topped corrugations 2. The corrugations 2 provided with fiat topsand troughs 3 and 4 repectively and inclined walls 15 are preferablyarranged in spaced groups separated by flat areas 4' with twocorrugations to a group. Where the corrugations are arranged in groupsas noted above, a small beaded portion 5 can, if desired, be disposedadjacent to the walls 15 of certain of the corrugations 2.

The opposed side marginal edges of each sheet 1 as noted particularly inFIGURES 2 and 3 have special configurations which enable the marginalside edge of one sheet to be properly overlapped by the oppositemarginal side edge of an adjacent and similarly shaped sheet. The oneside marginal edge generally designated by the reference numeral 6 ofeach sheet 1 comprises the portion of the lower sheet in the joint whichis lapped by the opposed marginal side edge 7 of the upper or lappingsheet. As indicated in FIGURE 2 marginal side edge 6 is provided with aupstanding curved bead 8. Bead 8 is joined to the upwardly and inwardlyinclined partial wall section 9 in such a fashion that portions of bead8 and wall section 9 form a sinuously curved recess 10. Joined to theWall section 9 is a second partial inwardly and upwardly inclined wallsection 11. Wall section 11 is advantageously inclined at a smallerangle to the normal horizontal bottom 3,041,784 Patented July 3, 1962plane A of the sheet 1 than wall section 9 the angle of wall section 9for example, being on the order of 50 and that of wall section 11 beingon the order of 229. Wall section 11 is joined at the point or crest 12to a downwardly and outwardly inclined full wall section 13. Wallsections 9, 11 and 13 roughly form an inverted V-shaped marginalcorrugation. The marginal side edge 6 is completed by means of themarginal flange 14. During manufacture of a sheet 1, this flange isnormally directed upwardly a few degrees from the normal horizontalbottom plane A of the sheet 1 for a purpose to be hereinafter described.

As indicated in FIGURE 3, the opposing side edge 7 of the sheet 1comprises a fiat-topped marginal corrugation 2 provided with fulldiverging walls 15 and 15. Corrugation 2' has the same generalconfiguration, pitch, depth area for the flat top 3 and angle ofinclination for its walls as the remaining flat-topped corrugations 2 ofthe sheet 1 except for wall 15. In the case of the outermost wall 15 ofthe corrugation 2', which corrugation constitutes the lapping part ofthe upper sheet 1 of the joint, this Wall is purposely over-bentinwardly a few degrees from the normal angle of inclination (shown indotted lines in FIGURE 3) of the other corrugations 2. Thus instead ofbeing at an angle of 50, for example, like the other diverging Walls 15of corrugations 2, it is inclined at an angle of 55 with respect to lineA as indicated in the drawings. In other words, if wall 15' had the sameangle of inclination as the walls of the remaining upstandingcorrugations 2 of the sheet, it would assume the position shown indotted lines in FIGURE 3. The side edge 7 of the sheet finallyterminates in a sinuously curved lip 16 joined to the bottom extremityof wall 15'.

During installation of the roofing sheets 1 it is contemplated thatthese sheets would be placed side by side in such a fashion that themarginal side edge 6 of one sheet 1 would be overlapped by the opposingmarginal side edge 7 of a similarly shaped sheet 1. The manner in whicha plurality of sheets 1 are overlapped will now be described withparticular reference being made to FIGURE 4 which shows a typicalinstallation. The roofing sheets 1 are placed side by side and crosswaysupon the conventional roofing supports 18 in such a fashion that thesinuously curved lip 16 on the Wall 15 of the corrugation 2' of theupper or lapping sheet is snugly received in the sinuous recess 10 ofthe lower or lapped sheet 1. The partial wall section 9 of the lappedsheet is disposed as noted above at an angle to the horizontal line Agenerally corresponding to the normal angle of inclination of the maincorrugations 2 and it is this portion of the lapped sheet which directlycontacts the overly bent wall 15 of the corrugation 2' of the lappingsheet. Due to the over-bending of the wall 15 during manufacture, wall15 will always tend to maintain surface to surface contact with thepartial wall section 9 during expansion and contraction of the roofingsheets. This tensioning of wall 15 against wall section 9 has a furtheradvantage in that it causes lip 16 of the lapping sheet to maintaincontact partly with head 8 and partly with wall section 9 of the lowersheet and to remain in the sinuous anti-siphoning recess 10. Theconfiguration of recess 10 and lip 16 acts to prevent water and moisturefrom seeping through the joint to the roofing supports 18.

It will be further observed by reference to FIGURE 4 that the secondpartial wall section 11 of the lapped sheet is out of contact with theupstanding marginal corrugation 2 of the lapping sheet except at thepoint or crest 12 where partial wall section 1 1 meets the downwardlyinclined full wall section 13 of the lapped sheet while the full wallsection 13 is in contact with the innermost wall 15 of the corrugation2' of the upper sheet for the full length of said innermost wall 15. Thepurpose of the particular configuration and arrangement of partial wallsection 11 with respect to the corrugation 2 of the upper sheet 1 istwo-fold. It provides, first of all, a nonsiphoning air pocket 20between the corrugation 2' of the lapping sheet and wall section 11 ofthe lapped sheet. Air pocket 20 acts in conjunction with lip 16 andrecess to prevent the entrance of moisture and water between the lappedand lapping sheets at their point of juncture. Secondly, since the crest'12. of the lapped sheet contacts the underside of the flat top 3' ofthe corrugation 2 of the lapping sheet at substantially the point ofintersection between the flat top 3 and the wall of the corrugation 2 orat a point which is offset from the center of the flat top 3', the sheetfasteners or nails 21 are advantageously driven only through onethickness of metal at a time during installation of the sheets. Thisprovides for ease in installation. Partial wall section 9 because of itsparticular configuration and angle of inclination, also advantageouslyacts to guide the wall 15' and lip 16 of the lapping sheet into properposition in the joint. By forming the marginal side edge 6 of the lappedsheet in the manner proposed such as by using partial wall sections 9and 1 1 instead of a full wall section, a top such as flat top 3 can beeliminated and a minimum amount of material is used in forming this sideedge of the sheet in addition to providing the other advantageous jointfeatures mentioned above.

The flange 14 of the lapped marginal side edge 6 is purposely directedupwardly a few degrees from the horizontal during manufacture as notedabove. The purpose of this is to maintain line or surface to surfacecontact between this flange and a trough portion 4 of the upper orlapping sheet during installation so as to compensate for any tolerancesthat may exist in flange 14 during manufacture, it being extremelydifficult if not impossible to maintain such tolerances on standardcorrugating machines presently in use. When the sheets 1 are overlapped,flange 14 will tend to flatten out under the pressure exerted thereonduring nailing down of the sheets. Flange 14 will always maintaincontact with the lapping sheet despite expansion and contraction of thesheets under all ordinary conditions of installation. A small troughwill ordinarily exist between flange 14 of the lower sheet and through4" of the upper or lapping sheet. This adds to the resilientcharacteristics of flange 14 in maintaining contact with the lappingsheet.

A further advantage in the use of the lap joint of the instant inventionresides in the fact that it is possible to nail first either through theoutermost corrugation 2' of the lapping sheet which contacts the wallportions 9., 11 and 13 of the lapped sheet, or through the nextcorrugation 2 which does not contact wall portions 9, 11 and 13 but isadjacent thereto.

The particular lap joint of the instant invention also makes it'possibleto conveniently lap the ends of sheets 1 in super-jacent or upper rowson the wall or roof of the building with the sheets in the higher rows,the higher rows of sheets being generally indicated in dotted lines inFIGURE 4. In other words, the sheets 1 are so installed that the lapjoints of all the rows of sheets 1 constituting a particular roofcovering would be continuous rather than being oifset with respect toeach other and with the siphoning troughs formed by the sinuous recesses10 always being in alignment from the cave to the ridge portion of aroof structure.

The sheets 1 are installed in a conventional fashion on a buildingstructure. In the instant case therefore a lower sheet 1 is first nailedcrossways on the supports 18. A second upper sheet 1 is then installeddirectly above the lower sheet such that the opposing end edges of thetwo sheets overlap and nest with each other. If necessary, additionalsheets are installed directly above the second sheet in the same fashionas noted above. After the complete first line of vertically disposed andlapped sheets has been installed the second and adjacent line of lappingsheets is installed starting from the bottom of the structure beingcovered. As this second line of lapping sheets is installed the sideedges 7 of the lapping sheets are lapped over the side edges 6 of thelapped sheets at the same time that the opposing end edges of thelapping sheets in this second line are overlapped and nested with eachother. During installation therefore, the end edges of any horizontalline of sheets 1 will be in alignment and the side edges of any verticalline of sheets 1 will also be in alignment.

An advantageous embodiment of the invention has been herein disclosedand described. It is obvious that various changes and modifications maybe made therein without departing from the spirit and scope thereof asdefined in the appended claims wherein What is claimed is:

l. A weatherproof lap joint for roofing sheets comprising a pair ofroofing sheets overlapped at their marginal side edge portions, theoverlapping edge portion of the upper sheet having an upstandingmarginal corrugation provided with a substantially flat top and a pairof downwardly and outwardly inclined full walls, the outermost wall ofthe said corrugation terminating in a sinuously curved lip, theoverlapped edge portion of the lower sheet having sinuously bentportions including a bead defining a sinuous recess within which thesinuously curved lip of the upper sheet is snugly received, said lowersheet also having an upwardly and inwardly inclined partial wall sectionfor engaging a part of the outermost wall of the corrugation of theupper sheet and a second upwardly and inwardly inclined partial wallsection connected to and disposed at a difl'erent angle to thehorizontal from said first-mentioned partial wall section, saidlastmentioned wall section normally being out of contact with thecorrugation of the upper sheet, and a downwardly and outwardly inclinedfull wall sectionon said lower sheet connected to said second-mentionedpartial wall section, said full wall section being normally in contactwith the innermost wall of the corrugation of the upper sheet and forthe full length of the said innermost wall, the point of juncturebetween said full wall section and said second-mentioned partial wallsection comprising a crest in contact with the underside of the flat topof the corrugation of the upper sheet at a point which is offset fromthe central portion of said flat top, said crest serving as a supportfor the corrugation of the upper sheet and said full wall section of thelower sheet terminating in a flange which resiliently contacts theunderside of a trough in the upper sheet.

2. The lap joint as defined in claim 1 wherein said upper sheet isprovided with a plurality of symmetrical and uniform corrugationsincluding said marginal corrugation and wherein the outer wall of saidmarginal corrugation is over-bent inwardly during manufacture wherebysaid outer wall of said marginal corrugation will always be undertension when it contacts the first-mentioned partial wall section of thelower sheet.

3. The lap joint as defined in claim 1 wherein the flange of the lowersheet is bent upwardly during manufacture whereby as it engages theunderside of the trough in the upper sheet and tends to flatten outduring this engagement it still maintains contact with the upper sheet.

4. A roofing structure comprised of a plurality of similarly shapedcorrugated roofing sheets, each of said sheets having a plurality ofgenerally symmetrical and uniform corrugations and similar opposingmarginal side edge portions, the marginal side edge portion of one sheetbeing overlapped by the opposing marginal side edge portion of theadjacent sheet and forming a lap joint therebetween, the overlappingside edge portion of the upper sheet in said joint having an upstandingmarginal corrugation provided with a substantially flat top and a pairof downwardly and outwardly inclined full walls, the outer wall of saidmarginal corrugation .terminating in a sinuously curved lip, theoverlapped mar- 5 ginal side edge portion of the lower sheet in saidjoint having sinuously curved portions including a bead defining asinuous recess within which the sinuously curved lip of the upper sheetis snugly received and an upwardly and inwardly inclined partial wallsection for engaging the lower part of the outer wall of the marginalcorrugation of the upper sheet, said lower sheet also having a secondupwardly and inwardly inclined partial wall section connected to saidfirst partial wall section and normally out of contact with the marginalcorrugation of the upper sheet, a downwardly and outwardly inclined fullwall section connected to said second-mentioned partial wall section,said full wall section being normally in contact with the innermost wallof the marginal corrugation of the upper sheet and for the full lengthof the said innermost wall, the point of juncture between the full wallsection and the second-mentioned partial wall section of the lower sheetcomprising a crest which engages the underside of the flat top of themarginal corrugation of the upper sheet at a point which is offset fromthe center of the said top, said full wall section of the lower sheetterminating in a flange which contacts the underside of the upper sheetand fasteners driven through the flat top of the marginal corrugation ofthe upper sheet and the second partial wall section of the lower sheetand then through roofing supports so as to anchor said sheets to thesupports.

5. A roofing structure as defined in claim 4 wherein the outer wall ofthe marginal corrugation of the upper sheet is over-bent inwardly duringmanufacture whereby said over-bent outer wall will normally be undertension when it contacts the first-mentioned partial wall section of thelower sheet.

6. A roofing structure as defined in claim 4 wherein the flange of thelower sheet is bent upwardly during manufacture whereby as it engagesthe underside of the upper sheet and tends to flatten out during thisengagement it still maintains contact wth the upper sheet.

References Cited in the file of this patent UNITED STATES PATENTS1,072,508 Roth Sept. 9, 1913 1,833,456 De Gant Nov. 24, 1931 1,889,784Harter Dec. 6, 1932 2,073,706 Overholtz Mar. 16, 1937 2,099,752 RennerNov. 23, 1937

